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JavaScript: Replace the first digit in a string (should contains at least digit) with $ character

JavaScript Basic: Exercise-136 with Solution

Write a JavaScript program to replace the first digit in a string (should contains at least digit) with $ character.

Pictorial Presentation:

JavaScript: Replace the first digit in a string (should contains at least digit) with $ character.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Replace the first digit in a string (should contains at least digit) with $ character</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function replace_first_digit(input_str) {

  return input_str.replace(/[0-9]/, '$');
}
console.log(replace_first_digit("abc1dabc"));
console.log(replace_first_digit("p3ython"));
console.log(replace_first_digit("ab1cabc"));   

Sample Output:

abc$dabc
p$ython
ab$cabc

Flowchart:

Flowchart: JavaScript - Replace the first digit in a string (should contains at least digit) with $ character

ES6 Version:

function replace_first_digit(input_str) {

  return input_str.replace(/[0-9]/, '$');
}
console.log(replace_first_digit("abc1dabc"));
console.log(replace_first_digit("p3ython"));
console.log(replace_first_digit("ab1cabc"));

Live Demo:

See the Pen javascript-basic-exercise-136 by w3resource (@w3resource) on CodePen.

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Previous:Write a JavaScript program to remove all characters from a given string that appear more than once.
Next: Write a JavaScript program to test if a given integer is greater than 15 return the given number, otherwise return 15.

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JavaScript: Tips of the Day

Checks if a string is an anagram of another string (case-insensitive, ignores spaces, punctuation and special characters)

Example:

const isAnagram = (str1, str2) => {
  const normalize = str =>
    str
      .toLowerCase()
      .replace(/[^a-z0-9]/gi, '')
      .split('')
      .sort()
      .join('');
  return normalize(str1) === normalize(str2);
};
console.log(isAnagram('iceman', 'cinema')); // true

Output:

true